Question

This is the example string:

User.status <> 'actived'

I want this:

`User`.`status` <> 'actived'

But with the following regex:

/([a-z_]+[a-z0-9_]+)/i

The result is:

`User`.`status` <> '`actived`'

A context code usage:

protected function escapeExpression($expression)
{
    //$expression = "User.status <> 'actived'";
    //escapeKeyword returns '`' . $param . '`'
    return preg_replace('/([a-z_]+[a-z0-9_]+)/i', $this->escapeKeyword('$1'), $expression); 
}

Answer 1

/(?<!['a-z0-9_])([a-z_]+[a-z0-9_]+)(?!['a-z0-9_])/i would do the trick, using a negative lookbehind and a negative lookahead.